1. Field of the Invention
The present invention relates to a face authentication system and an authentication method thereof; and, more particularly, to a face authentication system including a photographing unit equipped with an auto focus lens, a distance extraction unit, and a feature extraction unit, and an authentication method thereof.
2. Description of the Related Art
In general, a face authentication system refers to a system used to perform personal authentication through the face of an authentication target person. Such a system is used for personal identification when the authentication target person enters a specific building or a specific place within the building.
A recently used face authentication system employs a feature point extraction scheme for photographing the face of an authentication target person, registering feature points of the face, which are capable of identifying the authentication target person, as registration data, extracting feature point data of the face through re-photographing of the authentication target person when authenticated, and deciding whether or not the authentication target person is right through comparison of the registration data with the feature point data.
However, the face authentication system employing such a feature point extraction scheme is sensitive to lighting and expression variation, and has many problems such as some recognition reduction deterioration and mis-recognition, which result from disguise, beard change, wearing of glasses or a hat, and facial shape change due to a plastic operation.